Giraffidae from the Middle Miocene Hominoid Locality of Çandır (Turkey)

Giraffidae from the Middle Miocene Hominoid Locality of Çandır (Turkey)

Giraffidae from the middle Miocene hominoid locality of Çandır (Turkey) Denis Geraads, Fehmi Aslan To cite this version: Denis Geraads, Fehmi Aslan. Giraffidae from the middle Miocene hominoid locality of Çandır (Turkey). Courier Forschungsinstitut Senckenberg, 2003, 240, pp.201-209. halshs-00009917 HAL Id: halshs-00009917 https://halshs.archives-ouvertes.fr/halshs-00009917 Submitted on 3 Apr 2006 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. 1 Giraffidae from the middle Miocene hominoid locality of Çandır (Turkey). 1 figure, 2 plates Denis GERAADS * and Fehmi ASLAN ** *UPR 2147 CNRS - 44 rue de l'Amiral Mouchez, 75014 PARIS, FRANCE [email protected] ** MTA Genel Müdürlügü, Jeoloji Etüdleri Dairesi, 06520 ANKARA, TURKEY Abstract.- The site of Çandır has yielded one of the best collections of Giraffidae from the Middle Miocene of the Eastern Mediterranean. It is here referred to a single new species, whose comparison with other contemporaneous remains from this area and the Siwaliks raises some interesting phylogenetic problems. Key-words.- Middle Miocene, Turkey, Mammalia, Artiodactyla, Giraffidae Introduction The Middle Miocene locality of Çandır (Ankara, Kalecik, Turkey) is well known for having yielded the hominoid primate Griphopithecus alpani (TEKKAYA, 1974). Çandır was excavated by the late I.TEKKAYA (collection in the MTA Museum, Ankara, labelled AÇH or MTA) and, from 1989 onwards, by E.GÜLEÇ (collection in the Department of Anthropology, Dil ve Tarih Cografya Fakültesi, Ankara, labelled ÇA). The present study is based upon both collections. E.GÜLEÇ'S material is precisely registered, especially as to the exact provenance 2 from one of the several Çandır localities, but this is not always the case with TEKKAYA'S, for which sometimes only the bone preservation and color can indicate something about a likely origin, usually with much doubt; this uncertainty is not of great consequence, however, since there does not seem to be any significant difference, neither in size nor in morphology, between the two main fossiliferous spots. These are Locality 1 mainly excavated by I.TEKKAYA, and Locality 3 mainly excavated by E.GÜLEÇ. Materials and Methods Systematic description Giraffokeryx PILGRIM, 1910 Diagnosis: COLBERT 1935: 329. Type-species: G.punjabiensis PILGRIM, 1910 Giraffokeryx anatoliensis n.sp. Holotype : Rear part of a skull with the left post-orbital horn, N° ACHÜ-308, from Çandır locality 1, kept in the MTA Museum, Ankara (Pl.1, Fig. 1). Derivatio nominis: from Anatolia. Diagnosis: A species of Giraffokeryx which differs from the type-species by its shorter and less inclined horns, more salient occipital crest, and p3 always with oblique epicristid. Hypodigm : All teeth of Giraffokeryx from Çandır, even isolated ones, can easily be identified, but this is not always the case for limb bones, which are only slightly larger, on average, than those of Palaeomeryx. For them, the identifications are only the most likely ones. 3 Plate 1 about here Description a) Skull On the holotype, the left horn is inserted above the post-orbital bar. No suture or line marks its limit from the hollowed frontal bone. Thus, the horn may either be an outgrowth of the frontal bone, or an originally independent bone, but fused because of the old age. It is very wide antero-posteriorly at the base, but rather compressed transversely; its lower part was strongly divergent from its counterpart, but the divergence lessens towards the tip, the horn being curved inwards. However, it is not inclined backwards, in contrast to Giraffokeryx punjabiensis from the Middle Miocene of Pakistan, which has also longer horns (COLBERT 1933). The tip is rounded rather than pointed, and there are some faint knobs, especially along the anterior border. Another difference with the Siwalik species is the backward protrusion of the supra-occipital crest, shelf-like at the base, but quickly becoming subdivided into two horn-like expansions, continuing the paired pillars of the occipital face. The occipital crest is always rather salient in giraffids, including G. punjabiensis, but never to this extent, which is reminiscent of Ampelomeryx ginsburgi DURANTHON & AL., 1995, from the early Miocene of Western Europe (see below). Given the importance of cranial appendages in Ruminant taxonomy, and the lack of evidence of intra-specific variability, we believe that these differences are sufficient to distinguish specifically the Turkish species from the South Asiatic one. Other characters of the skull are reminiscent of those of G.punjabiensis, or of other Middle Miocene Giraffids, such as Injanatherium arabicum MORALES & AL., 1987, from Saudi Arabia. The condyles are large, the bicondylar width being greater than the minimum width of the occipital, which is strongly constricted at mid-height ; the basioccipital is rather wide anteriorly, but the anterior tuberosities are not more salient than in I. arabicum. A 4 primitive character, shared by Canthumeryx from the Middle Miocene of Jebel Zelten, Libya (HAMILTON 1973, 1978) but no longer present in later Giraffids, is that the mastoid still separates the post-tympanic apophysis of the squamosal from the paroccipital process of the occipital. Dimensions : G.anatoliensis I.arabicum G.punjabiensis Distance from front of orbit to occipital condyle 230 205 ? - Maximum width across post-orbital horns 2 x 150 - 403 Width of braincase 98 - - Minimum width across temporal lines 56 35 56 Bicondylar breadth 81 72 76 Distance between tips of paroccipital processes 84 ±75 88 Maximum occipital width 133 128 144 Height of occip. (base of fo.magnum to occ.crest) 111 101 - Another fragment of skull, AÇH-204, had no horn in front of the orbit, contrary to G.punjabiensis, which has 4 horns, but as it seems to have no supra-orbital horn either, it might be of a female, and no conclusion can be drawn as to the presence of ante-orbital horns in males. b) Teeth Upper teeth are little different from those of Upper Miocene Palaeotragus, but they are more brachyodont, and the anterior lobe of DP3 is longer. The premolars are not very large, 5 molars usually have no entostyle, almost no cingulum, and outer ribs and styles are moderate. Thus, they are rather different from those of Canthumeryx. Dimensions : ÇA 91-78 (Loc.3) DP2-DP4 = 58.5 ÇA 93-69 (Loc.3) DP4 length = 24 ÇA 92-9 (Loc.3) M1-M3 = 72.4 ÇA 94-34 (Loc.3) M1-M3 = 79 ÇA 92-187 (Loc.3) P3-M2 = 82.8 ÇA 90-30 (Loc.3) M3 = 27 x 27 AÇH-204 M1-M3 = 71 The lower incisors are present on an almost complete but imperfectly preserved mandible (ÇA 94-115). They are about as large as the isolated canines. There are 5 specimens of the latter tooth which all are clearly bilobed. The diastema is slightly shorter than the tooth row. There are more than 30 lower premolars, many of them in mandibular fragments (Pl. 1, Fig. 2-3, and Pl. 2). They are variable, but not extremely so, and perhaps less so than at Paşalar. DE BONIS & al. (1997: 127) may have been right in suggesting that more than one species was present there. The p3 always has the paraconid well separated from the parastylid; they may tend to fuse lingually. On only 2 teeth out of 12 does the metaconid extend forwards, meeting the base of the paraconid, and the crest joining the protoconid to the metaconid (epicristid of VANDEBROEK'S nomenclature) is always oblique backwards. This oblique crest often incorporates the entoconid, leaving only a short intermediate crest (telocristid) between it and the rearmost one (posterior arm of the eocristid). On p4 (20 specimens), the metaconid 6 is always expanded into a lingual wall blocking the anterior valley, which may remain open lingually at Paşalar (GENTRY 1990, fig.5C). The posterior end of the protoconid is always bifurcated; its labial arm (eocristid) is interrupted before reaching the hypoconid on unworn teeth; its lingual arm (epicristid) is always posterior and oblique. Plate 2 about here The limited range of variation of the premolars of Giraffokeryx anatoliensis strongly suggests that the Siwalik premolars assigned to G. punjabiensis are too variable to be accommodated within a single species. For instance, a p4 figured by PILGRIM (1911, pl.2, fig.1) has a very large anterior lobe (paraconid + parastylid) closed lingually, while that of the skull figured by COLBERT (1933, 1935) has no anterior lobe, as in Çandır. Similarly, the p3s figured by PILGRIM (1911, pl.2, fig.2, 3) have transversal crests, while COLBERT (1935: 339) states that: "the internal border of the third premolar may be closed or open." The Çandır sample of lower premolars provides a new evidence of the normal variability of giraffid premolars, which seems to confirm the previous hypothesis (GERAADS 1989) that apparent large variability may in some cases result from a mixing of taxa. Lower molars display the same characters as at Paşalar (GENTRY 1990): weak or absent ectostylids, no Palaeomeryx-fold, the third lobe of m3 forming a complete loop; the latter looks larger than at Prebreza. Dimensions: AÇH-1290 p2-m3 = 137 p2-p4 = 57.5 m1-m3 = 80 ÇA 92-4 (Loc.1) 141.5 62.5 85 ÇA 94-115 (Loc.3) 78 i1-m3 = 306 7 AÇH-1295 64.5 MTA no N° 78.5 AÇH-2 77.5 AÇH-1287 89 MTA no N° 83 L base m3 = 38 ÇA 93-39 (Loc.3) 38.5 ÇA 93-3 (Loc.3) 36 AÇH-1 p3-p4 = 41.5 AÇH-7 41 80 ÇA 92-36 (Loc.3) L dp3 = 17.5 L dp4 = 28.3 L m1 = 24.4 dp2-dp4 = 61.8 ÇA 92-24 (Loc.3) 17.3 25.5 22.5 ÇA 92-28 (Loc.3) 27 24 AÇHÜ-1293 18.7 28.9 MTA no N° 17.8 27 Lower canines (lingual height x lingual width) : 15 x 10; 15 x 10.8; 16.7 x 11.9; - x 10.8.

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